Leslie Horn

For the first time, scientists have produced human embryonic stem cells (hESCs) using 3D printing. They're utterly amazing, and they could be used to reproduce kidneys, hearts, and other organs in the future.

A team at Heriot-Way University in Scotland loaded up stem cells as ink for the 3D printer, and using a valve, pushed out living cells into droplets of new cells in uniform sizes. The researchers would adjust the nozzle on the printer to control the very diameter of the cells. And what's even cooler is these the organisms were capable of differentiation, meaning they can form into various types of tissues. Other tries at this replication have not worked as well because they've produced unstable results. However, 99 percent of the cells that came out of the printer were still usable.

So why is this important? hESCs are like blank slates, meaning they can be used to create any type of tissue. Think lung transplants, liver transplants, skin grafts, and so forth. Or 3D printed cells could be planted into existing organs to help regenerate parts that have been damaged. And furthermore, it would mean a limit on animal testing. Because rather than testing on these live critters, scientists could use real, 3D printed organs for drug trials. It's totally ok to be in awe of 3D-printed scissors, but this development is on an entirely different plane of amazing. [PopSci]